Cartilage and other connective tissue in cartilaginous joints can break, fracture, or otherwise become damaged due to injury, age, heredity, or combinations thereof, resulting in pain and/or loss of motion. Often, treatments for such conditions are ineffective in alleviating the pain, or require a long recovery.
For example, hyaline cartilage that covers the surface of bones forming a load-bearing joint allows pain free motion at the joint and absorbs loads placed across the joint during activities of daily living. But these cartilage surfaces can experience wear and damage due to trauma or osteoarthritis, or other factors such as obesity and poor joint surface alignment, and the exposed bone surfaces can cause significant pain in the joint upon motion. Moreover, the loss of the cartilage surface can diminish its shock absorption capability, which can result in excessive loads being placed across the joint and lead to further damage to the cartilage surfaces and increasing patient symptoms. Reducing load across the joint is an effective way clinically of reducing the level of pain in the patient, and can be accomplished by several methods, including weight loss, surgery to realign the anatomy, and, in cases of severe cartilage loss or wear, replacement of the joint. However, weight loss may be difficult or slow to achieve, and it may take time before it results in a reduction in load or alleviation of pain. Further, surgery or joint replacement does not leave the joint intact and requires a long recovery time.
As another example, cartilage and components of the intervertebral disc between vertebrae can degenerate, resulting in pain and pressure on the spinal cord. Traction methods are meant to relax the soft tissue and separate spinal vertebral segments, therefore creating negative intra-disc pressure, retracting bulging discs, and removing impingements on nerves. However, while methods and devices for supplying traction forces are generally known, they do not provide consistent, continuous low magnitude traction forces in order to maintain disc height and health and to relieve acute and chronic cervical neck pain. In addition, current apparatuses and methods for fixation or fusion of bones and joints to promote healing, relieve pain, and/or reduce future injury of other cartilaginous joints are often insufficient to provide proper stability or otherwise aid in healing or treating the bones and connective tissues involved.
Thus, there remains a need in the art for an intervention that effectively reduces loading in cartilaginous joints and that does not substantially alter the anatomy of the joint, thereby requiring a more effective treatment and shorter time to recover.